In the most recent Report to the Surgeon General, the number of deaths associated with tobacco use was estimated to be about 390,000 in 1985. The list of related disorders includes certain cancers, heart disease, respiratory disease, stroke, stomach ulcers, and impaired fetal outcome. Since tobacco and its smoke contain approximately 4,000 compounds, it is not an easy matter to delineate the deleterious effects of individual compounds. For several reasons, nicotine and its metabolites warrant special study. Nicotine is the principal alkaloid in tobacco. It has wide and diversified pharmacological activities on the peripheral and central nervous systems and on the cardiovascular, endocrine, gastrointestinal and skeletal motor systems. Nicotine is addictive and largely responsible for the compulsive use of tobacco products. Since it occurs naturally only in tobacco, exposure to such products can be monitored in physiological fluids by determining the presence of nicotine and its metabolites. Currently, nicotine per se is being prescribed for therapeutic purposes (i.e. as an aid in smoking cessation) in the form of gum, aerosols and dermal patches. Only a small number of nicotine metabolites have been quantified in pharmacokinetic, pharmacodynamic nad epidemiological studies. Fewer still have been examined for toxicological effects at the sub-chronic doses commonly encountered during normal tobacco use. In general, the metabolites commonly studied are those that are most abundant and easily quantified, e.g. cotinine. There is a need to have specific, sensitive and rapid assays that can detect and quantify additional metabolites in order to evaluate their biological significance in vivo and in vitro systems. The metabolism of nicotine is complex and leads to the formation of several products via different enzymatic routes. The specific aims of this project are to produce antibodies and develop immunoassays for metabolites that warrant further study: (1) the isomers of nicotine N'oxide; (2) the adducts formed between the active intermediate of the cytochrome P450 reaction (the nicotine Delta1'(5') iminium ion) and nucleophilic groups on macromolecules; and (3) the nicotine isomethonium ion.